#pragma once
#include "requestor.hpp"
#include <unordered_map>


namespace rpc
{
    namespace client
    {
        class TopicManager
        {
        public:
            using ptr = std::shared_ptr<TopicManager>;
            using SubCallback = std::function<void(const std::string& key,const std::string& msg)>;
            TopicManager(const Requestor::ptr& requestor) : _requestor(requestor)
            {}
            bool create(const BaseConnection::ptr &conn, const std::string &key) 
            {
                return commonRequest(conn, key, TopicOptype::TOPIC_CREATE);
            }
            bool remove(const BaseConnection::ptr &conn, const std::string &key) 
            {
                return commonRequest(conn, key, TopicOptype::TOPIC_REMOVE);
            }
            bool subscribe(const BaseConnection::ptr& conn,const std::string& key,const SubCallback& cb)
            {
                addSubscribe(key, cb);
                std::unique_lock<std::mutex> lock(_mutex);
                bool ret = commonRequest(conn,key,TopicOptype::TOPIC_SUBSCRIBE);
                if(ret == false)
                {
                    delSubscribe(key);
                    return false;
                }
                return true;
            }
            bool cancel(const BaseConnection::ptr& conn,const std::string& key)
            {
                delSubscribe(key);
                return commonRequest(conn, key, TopicOptype::TOPIC_CANCLE);
            }
            bool publish(const BaseConnection::ptr &conn, const std::string &key, const std::string &msg)
            {
                return commonRequest(conn, key, TopicOptype::TOPIC_PUBLISH, msg);
            }
            void onPublish(const BaseConnection::ptr &conn, const TopicRequest::ptr &msg)
            {
                //1. 从消息中取出操作类型进行判断，是否是消息请求
                auto type = msg->optype();
                if (type != TopicOptype::TOPIC_PUBLISH) 
                {
                    ELOG("收到了错误类型的主题操作！");
                    return ;
                }
                //2. 取出消息主题名称，以及消息内容
                std::string topic_key = msg->topicKey();
                std::string topic_msg = msg->topicMsg();
                //3. 通过主题名称，查找对应主题的回调处理函数，有在处理，无在报错
                auto callback = getSubscribe(topic_key);
                if (!callback) 
                {
                    ELOG("收到了 %s 主题消息，但是该消息无主题处理回调！", topic_key.c_str());
                    return ;
                }
                return callback(topic_key, topic_msg);
            }
        private:
            void addSubscribe(const std::string &key, const SubCallback &cb) 
            {
                std::unique_lock<std::mutex> lock(_mutex);
                _topic_callbacks.insert(std::make_pair(key, cb));
            }
            void delSubscribe(const std::string &key) 
            {
                std::unique_lock<std::mutex> lock(_mutex);
                _topic_callbacks.erase(key);
            }
            const SubCallback getSubscribe(const std::string &key) 
            {
                std::unique_lock<std::mutex> lock(_mutex);
                auto it = _topic_callbacks.find(key);
                if(it == _topic_callbacks.end())
                    return SubCallback();
                return it->second;
            }
            bool commonRequest(const BaseConnection::ptr& conn,const std::string& key,TopicOptype type,const std::string& msg = "")
            {
                //1.构造请求对象
                auto msg_req = MessageFactory::create<TopicRequest>();
                msg_req->setid(UUID::uuid());
                msg_req->setmtype(Mtype::REQ_TOPIC);
                msg_req->setTopicKey(key);
                msg_req->setOptype(type);
                if(type == TopicOptype::TOPIC_PUBLISH)
                    msg_req->setTopicMsg(msg);
                //向服务端发生请求，等待响应
                BaseMessage::ptr msg_rsp;
                bool ret = _requestor->send(conn,msg_req,msg_rsp);
                if(ret == false)
                {
                    ELOG("主题操作请求失败！");
                    return false;
                }
                auto topic_rsp_msg = std::dynamic_pointer_cast<TopicResponse>(msg_rsp);
                if(topic_rsp_msg.get() == nullptr)
                {
                    ELOG("主题操作响应，向下类型转换失败！");
                    return false;
                }
                if (topic_rsp_msg->rcode() != Rcode::RCODE_OK) 
                {
                    ELOG("主题操作请求出错：%s", errReason(topic_rsp_msg->rcode()).c_str());
                    return false;
                }
                return true;
            }
        private:    
            std::mutex _mutex;
            std::unordered_map<std::string,SubCallback> _topic_callbacks;
            Requestor::ptr _requestor;
        };
    }
}